Because job interviews are so nerve-wracking, we often spend days or weeks preparing. But it's almost impossible to predict which questions you'll be asked or how things will go.

Bernard Marr, a global enterprise performance expert and a best-selling business author, says in a recent LinkedIn post that preparing for an interview is difficult. “In most cases we practice the answers to a long list of possible questions. The problem is that this can leave you over-prepared, and as a consequence your pre-conceived answers can come across a bit robotic.”

Luckily, there are only three interview questions that really matter, Marr says. Preparing for these queries will allow you to answer almost any question more naturally because “you can link most interview questions back to these.”

“The interviewer might use many different questions and angles to get to the answers,” he adds. But these are the three questions they ultimately want answered:

1. Have you got the skills, expertise, and experience to perform the job?

Marr says to answer this one, you need to think about the key skills you might need for the job, and assess your own level of expertise and experience in that context. “It makes sense to identify the more specific or technical skills that your potential employer might expect as well as some more generic skills such as being a good communicator, having good IT skills, being a team player, etc.”

He says preparing for this question will help you answer many other interview questions (without getting “sidetracked into talking about things that are not relevant”), such as:

Tell me about yourself?

What are your greatest strengths / weaknesses?

What can you do for us that other candidates can’t?

Why do you think you are right for this job?

What do you think the main challenges will be?

2. Are you enthusiastic and interested in the job and the company?

All hiring managers want to know that you are interested in the company and excited about the prospect of working there, Marr explains. “You therefore want to demonstrate that you have researched the company, understand its strategy, current performance, structure, market position, and products and that you can’t wait to join them.” Show the potential employer you’ve done your homework, and demonstrate your enthusiasm for the job and company.

Here are other ways they’ll ask this question:

What do you know about our company?

What do you think our company is aiming to achieve?

What do you know about our products and services?

Why do you want to work for this company?

Why do you think this job is right for you?

What motivates you?

3. Will you fit into the team, culture, and company?

“This final key question is about your personality and your style and how you as a person fit into the team and culture of the company,” Marr says. Every company has its own unique culture, and it’s important to both you and the employer that you fit in.